1. Field of Invention
This invention relates to improvements in the joining of succeeding, relatively heavy, pipe sections within a trench and particularly to a light weight, portable, self-contained pipe joining device which is compact, economical and simple to operate and to the corresponding system or method of joining such pipe sections.
2. Prior Art
The art of joining succeeding pipe sections within a trench requires the positioning of two pipe sections approximately end-to-end and the exerting of an axial force to mate the male and female ends of the pipe sections. The evolution is complicated by the frequently limited width of the trench, the occasionally substantial depth of the trench, the instability of the trench walls, the presence of water within the trench and the massive size of the pipe sections to be joined.
For this purpose, contractors have utilized heavy machinery to position the succeeding pipe section and an array of internally and externally positioned tugging devices which were electrical, mechanical and gasoline driven powered and hydraulically actuated to axially move the succeeding pipe sections to effect abutment with the preceding pipe section.
Approaches that have been considered include an externally placed, motor driven, hydraulically actuated cylinder to which is attached a cable gripping device (note for example U.S. Pat. No. 3,639,967 to J. E. Brighton, issued Feb. 8, 1972) or an internally placed, battery powered, hydraulically actuated cylinder to which is attached a cable gripping device (note for example U.S. Pat. No. 3,486,214 to J. J. Curtis and R. M. Sandvick, issued Dec. 30, 1969) or an externally placed, manually powered, hydraulically actuated cylinder to which is attached a jacking rod (note for example U.S. Pat. No. 3,469,298 to R. R. Pizzagalli issued Sept. 30, 1969).
While all these approaches attempted to overcome the dilemmas of joining succeeding pipe sections, they failed to adequately solve the problem. In some instances, heavy external members were required to support the externally positioned pipe joining device, while in other instances the pipe joining device must be repositioned with each succeeding pipe section to be joined. In still other instances, a significant separate power source was required.
The present invention provides an alternate solution to the difficulties of the prior art. This alternate solution is new, not obvious to one skilled in the art and of great utility.
3. Summary Discussion of the Invention
It is therefore an object of the present invention to provide a light weight, portable, self-contained pipe joining device and system which may be operated by a single individual.
It is another object of this invention to provide a pipe joining device and system which is positioned internally in the preceding, initial pipe section and may remain stationary while joining a multiple number of succeeding pipe sections.
It is still another object of this invention to provide a pipe joining device and system which may join succeeding pipe sections without the assistance of heavy equipment to axially move the succeeding pipe section.
It is still another object of this invention to provide a pipe joining device and system which may be readily aligned with the intersection of the horizontal and vertical centerline of the preceding pipe section to facilitate positioning and mating of the succeeding pipe sections.
It is still another object of this invention to provide a pipe joining device and system which may be successfully used in confined areas with limited access.